


Double Bass

by BlueNeutrino



Series: Tricuspid [1]
Category: Supernatural
Genre: Blow Jobs, Cardiophilia, Dom Castiel, Dom/sub, Established Relationship, Heartbeat Kink, Heartbeats, M/M, Masturbation, Multi, Orgasm Denial, Sub Dean, Sub Sam, Threesome - M/M/M
Language: English
Status: Completed
Published: 2014-09-04
Updated: 2014-09-04
Packaged: 2018-02-16 03:57:20
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,241
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/2255007
Author URL: https://archiveofourown.org/users/BlueNeutrino/pseuds/BlueNeutrino
Summary: <blockquote class="userstuff">
              <p>Cas loves listening to both Sam and Dean's hearts, but now he has a game he wants to play with both of them.</p>
            </blockquote>





	Double Bass

**Author's Note:**

  * For [PetrichorPerfume](https://archiveofourown.org/users/PetrichorPerfume/gifts).



> I'm branching out from my usual Destiel cardiophilia fic, thanks to some excellent suggestions from PetrichorPerfume. I'm sure she'll see what the influences for this fic were.

Castiel stands at the foot of the bed, casting an appraising glance over his two boys sprawled across the mattress. A smile of approval curls on his lips as he takes in their naked forms, eyes roaming over each toned line of muscle, the hard definition of hips and collarbones, and most pleasing of all, their fat, swollen cocks. Both of them are being such good boys, hands obediently lying at their sides as they await his instruction. Cas moistens his lips with his tongue before he speaks. “Here’s how this is going to work,” he begins, reaching up to take the stethoscope he’s wearing from around his neck and place the ends in his ears. Unlike the Winchesters, he’s still fully dressed. “I want to hear your heartbeats. I want to know just how excited you both are and just how eager you are to please me. So, I’m going to take a listen.” He sits down on the edge of the bed beside Sam, who looks up at the angel’s impassive face with darkened eyes and parted lips. His chest shudders with each heavy breath he takes.

Cas raises the chestpiece, not bothering to warm it before setting the cold metal against Sam’s skin so that it partly obscures his anti-possession tattoo. Cas’ eyebrows inch closer together as he concentrates, moving the head of the stethoscope to several different points on Sam’s chest. The hunter’s heart is loud, thundering in Cas’ ears at a rapid pace, and the angel smiles. “Very good, Sam,” he praises as he pulls the stethoscope away, delighting in the proud look that settles on Sam’s face. “Now for Dean.”

He reaches over Sam’s body to get to the older brother, whose shoulders are pushed back and spine curved as he offers up his chest. “Relax,” Cas instructs, and a slow breath is expelled from Dean’s lungs as his muscles go slack. Castiel explores across his ribs with the chestpiece, frowning a little more than he had with Sam. Dean bites his lip. He’s so anxious to please and he hopes that his heartbeat sounds acceptable.

Cas focuses intently on the sound coming from inside Dean’s chest. It’s faster than his brother’s, but also quieter, and truth be told, Cas thinks Sam has the healthier heart. Dean’s is prone to skipping and bounding when he gets excited, but Sam’s is steadier; more robust. Each beat pumps more effectively so the rhythm doesn’t need to be as fast. It might be due to injury or illness one of them has received down the line, or it might simply be the natural differences between their bodies. Cas isn’t sure, but he does know that it makes for an interesting contrast.

“Beautiful, Dean,” Cas says eventually, and Dean looks both relieved and thrilled by the praise. “Now then,” Cas continues, standing up again and returning to the foot of the bed. “I want you to show me how hard your hearts can work for me and just how fast and strong you can get them to beat. When I say so, you’re both going to take your aching, needy cocks in your hands and start jerking off. I want to listen to your lovely little pumps while you pleasure yourselves. Don’t hold back; I want you to get your hearts beating as hard as you can, but neither of you is allowed to finish without my say so. When I tell you to stop, you take your hands off _immediately._ Then I’ll take another listen to your hearts, and whoever’s is working hardest will get a special treat. The other of you does not get to come tonight. Is that clear?”

“Yes, Castiel,” both reply in unison, respectfully using his full name as requested.

Castiel gives a satisfied smile. “Good,” he announces, casting his gaze between each of their faces. Sam is looking focused, but frustrated, clearly itching to get his hands on his cock. Dean, comparatively, looks nervous, chewing his bottom lip to hell. He seems to be straining under the pressure, and Cas finds it pleasing. He wants this experience to be a test for them. “Pick up your cocks,” he orders, and watches as they each move their right hands to close around their lengths. The rings of their thumb and forefingers come to rest an inch or so below the heads of their dicks, but each holds still, awaiting permission. Cas smiles at just how well behaved they are.

The brothers exchange a brief glance with each other, their expressions far less competitive than Castiel intended, but it doesn’t matter. He knows that Dean in particular likes to let his brother get off, and Sam, too, frequently lets his brother take more than his fair share of orgasms when Cas only permits one of them to come, but that’s the beauty of this game. Neither is aware of the other’s heart rate, and they both have only a small degree of control over their own. That makes it an entirely fair contest.

“You may begin,” Cas announces, and they each start to pump their fists furiously along their dicks. Castiel takes a moment or two to just enjoy the sight. Dean is moving faster, his strokes more shallow and knuckles blanching from the tightness of his grip. Sam, on the other hand, is moving his fist in longer strokes and twisting around the head, making each tug more forceful. It will be interesting to see from this which of them is expending most energy.

Castiel goes to listen to Dean first, preparing the stethoscope as he perches himself down on the edge of the bed. Dean has his eyes closed, but he feels the compression in the mattress as the angel sits down, and cracks them open again. Cas smiles down at him. It’s wonderful to watch the way Dean’s chest heaves as he works so hard, soft little grunts sounding in his throat and precome dribbling out onto his stomach. Even without listening to his heart, Castiel can tell how strained he is.

The angel begins by tracing Dean’s ribs with a fingertip before he places the stethoscope down. Dean’s chest is thinner than Sam’s. He has less solid muscle and there’s some rib definition down his sides, and Cas is sure that if Dean’s heartbeat was as powerful as his brother’s, his apex beat would be clearly visible. However, although he can’t quite see it, Cas is easily able to detect the pulse with his fingers before positioning the metal head of the stethoscope against it. The hammering of Dean’s heart thunders in his ears, rapid and forceful, and Cas can tell just how strongly Dean must be able feel it shaking his chest. The frantic beat is the result of combined exertion and excitement, and that pleases Cas immensely.

Cas doesn’t comment on it before he gets up and crosses round to Sam, not wanting to give away who might be winning. Sam is breathing more heavily than his brother, but not quite as quickly, and his jaw is clenched to stifle his grunts. Castiel reaches out to place the stethoscope on his heaving chest.

Sam’s heart is loud and powerful, the fierce percussion reverberating up the length of the stethoscope to pound on Cas’ eardrums. Right now, Cas would say it’s about the same pace as Dean’s, but there’s still some time to go. Their hearts are sure to get faster the closer they get to finishing; it’s just a case of who will get furthest before Cas orders them to stop.

The angel gives Sam a pleased smile and then stands to return to observing them from the end of the bed. It’s beautiful to watch. The pair of them are all frantic fingers, curling toes and arching spines as they pleasure themselves, their tugs punctuated by lewd moans and free hands grasping at the bedsheets. Cas can tell they’re both so, so close. Their balls are swollen and their cocks flushed purple from the strain. If he doesn’t end this soon, there’s going to be a mess to clean up.

Castiel delivers his order in one single, firm syllable. “Stop.”

It takes a second, but they obey, Sam momentarily before Dean.

“Hands off,” Cas reiterates so that they both place their hands by their sides again. One of them – Cas thinks it’s Dean – lets out a soft whine. Frustrated tension is evident on both their faces, but only one of them is going to get to relieve it tonight.

“So pretty,” Cas purrs, letting his gaze wander over both their bodies once more. There’s a faint bloom of pink spreading under Dean’s cheeks, accentuating his freckles, but Sam’s face isn’t so flushed. The veins of his cock, however, are standing out thick and throbbing as his engorged member begs for release. Cas licks his lips.

“Let’s see which of you worked hardest for me,” the angel says as he crawls onto the bed to kneel in the space between them. He begins with Sam, placing the stethoscope over his ribs once again. “Both of you take nice slow, deep breaths. In to the count of four, out to the count of three. I don’t want either of you cheating.”

It must be difficult for them both, but Cas feels the heaving of Sam’s chest steady beneath his hand as he continues to listen. Sam is staring up at him, blushing as they make eye contact, and Cas reaches up a hand to tenderly brush a strand of hair out of Sam’s face. The roots are slightly damp with sweat. “Well done, Sam,” Cas says with a smile. “Your heart sounds very loud and strong.”

The corners of Sam’s lips twitch in pleasure. He hasn’t been given permission to speak, but he chances it anyway. “Is it fast enough for you?”

Cas lets his boldness slide. “I don’t know yet,” he replies. “I haven’t listened to Dean’s.”

Off to his right, he can hear Dean’s breaths coming heavy and shuddering, and the angel immediately chastises him. “Get a handle on your breathing, Dean. If you don’t play fair, I’ll let Sam win by default.” Dean suddenly gulps down a breath and holds it, swallows, then nods his obedience as he resumes trying to breathe in line with Cas’ instructions. Castiel shifts the stethoscope from Sam’s chest to Dean’s and begins to listen.

Dean’s heartbeat is similarly fast to his brother’s, but the sound is duller and doesn’t quite have the same forceful kick of volume. Still, the rapid thrumming is very pleasing as Cas listens to the blood rushing through Dean’s heart. “Your heart’s certainly going wild, Dean,” Cas says as he pulls the stethoscope away and removes it from his ears. “But I think Sam wins this one.”

Dean groans and shuts his eyes, a look of disappointment passing over his features. He’s pleased Sam will get to come, but at the same time hopelessly frustrated that he won’t, and Cas watches the conflict play out on his face before Dean turns to bury his face in the pillows. His entire body shifts so that his still-hard cock presses against the mattress, but as long as he doesn’t try to rut, Cas will let him get away with it. The angel returns his attention to Sam, giving him a warm smile of pride. Sam smiles back, looking pleased that he’s going to get his reward, but at the same time there’s a hint of guilt that he’ll get to come and his brother won’t. Still, Cas isn’t going to change the rules of the game.

“Would you like to know what your special treat is, Sam?” Castiel asks as he reaches up to undo his buttons and start undressing himself. Sam nods enthusiastically. “I’m going to suck you off and I want you to come down my throat.”

Sam’s lips part as he lets out a soft gasp. His cock gives a throb. “Really, Cas? Thank you…” He seems genuinely excited and grateful despite feeling bad for Dean.

Cas has stood up again to finish peeling off his clothes. He sees that Dean has raised his head again to watch as he pushes his pants down, leaving him in just his boxers that have a growing damp spot on them where his erection strains against the material. “Do you know why you don’t get to come tonight, Dean?” Cas asks him.

Demurely, Dean nods. “Yes, Castiel.”

“Why?”

“Because my heart isn’t beating fast enough.”

“And why is that?”

“Because I didn’t work hard enough for you.”

Cas nods. “That’s right. So what do you need to do to make it up to me?”

“Make my heart beat faster.”

“Exactly,” Cas replies, pleased that Dean has so readily understood what he wants. “So, you’re not to touch your cock in any way, but you have my permission to do what you need to get your heart rate up.” Cas says that final line just as he pushes his underwear down, and he’s sure the sight of his stiffened cock springing free has just caused Dean’s heartbeat to quicken further.

Dean’s throat clenches as he swallows, then he clambers up off the bed with a “Yes, Castiel,” as he’s determined to make the most of his second chance. Cas returns his attention to Sam, who spreads out onto the vacated side of the bed and splays his legs to allow Cas access. He’s breathing heavily again, excitement painted clearly on his face.

Now naked, Castiel retrieves the stethoscope and fits it to his ears before kneeling between Sam’s legs. The tubing is just long enough to let him do this. “Hold this in place for me,” he instructs Sam, who grasps hold of the metal disc that Cas is pressing to his chest, and then the angel lowers his mouth to the head of Sam’s cock. He doesn’t close his lips around it immediately, but begins by extending his tongue to swirl around the tip and then presses it into Sam’s slit. Sam gasps, and Castiel hears the sound of his heart skipping. Encouraged, the angel runs his tongue over more of Sam’s length, gliding down to lick over his balls before running back up his shaft. Sam moans again.

Neither of them are paying much attention to what Dean’s doing, but in the background Cas can hear the sound of Dean’s breathing coming quick and heavy. Maybe he’s deliberately hyperventilating to increase his pulse, or maybe that’s just his body’s natural response to watching what they’re doing. Cas doesn’t consider it for long before he returns his attention to Sam, opening his mouth wide to sink down onto the hunter’s length and draw it to the back of his throat.

Sam’s cock is large, in fitting proportion to the rest of him, and it takes a moment for Cas to adjust as he sucks him in beyond the point of triggering his gag reflex. Sam moans in delight, throwing back his head, and the hard thudding of his heart fills Castiel’s ears. That only serves to make the angel more aroused, and he snakes a hand between his own legs to grasp his cock and start working himself. He begins to time his sucks in sync with his own strokes, bobbing his head a little, and Sam is already so close to the edge it doesn’t take much more to push him over.

Within seconds, Cas hears the crescendo inside Sam build to a stuttering peak, and then the hunter cries out and comes. The taste of him is salty yet sweet as it lands hot on Cas tongue, and Cas eagerly swallows it down, feeling the spurts keep time with Sam’s racing heart. When he lifts his mouth away again, he jerks himself hard and fast a few more times before he spills his own seed across the insides of Sam’s thighs. Then, the angel pulls the stethoscope away from Sam’s chest and rolls himself onto his back, the pair of them breathing heavily as they lie side by side.

Sam is given time to recover, but it’s only a few seconds before Cas sees Dean hovering in the corner of his vision again. The angel raises his head to look at him. “What is it, Dean?”

“Please, Castiel,” Dean replies, shyly casting his eyes down at the floor. “Will you listen to my heart again?” Of course, he wants Cas to take his pulse as soon as possible.

It isn’t taking Cas long to recover, and he nods. In any case, he wants to hear Dean’s heart again. “Alright. Come here.” He gestures with his hand so that Dean comes to lie down on the bed beside him, and then Cas props himself up on an elbow as he places the stethoscope once again on Dean’s chest. The sound that meets him is pleasing. Whether it was just the shallow breathing or the excitement from watching his angel blow his brother, Dean’s heart is racing. Cas smiles at him. “You have such an excited heart, don’t you? Now you’ve got it beating so hard for me, I think Sam deserves to hear it.” Cas twists his neck to look at the younger Winchester brother, who’s already turned his head slightly to watch them both. “Sam, would you like to listen to your brother’s heartbeat?”

Sam nods, his eyes making contact with Dean’s. “Yes, please.”

Both he and Dean shuffle closer to Cas, so that the angel removes the earpieces and fits them onto Sam before stretching the stethoscope across his own body. He presses the head against Dean’s chest and holds it in place. Both brothers are nestled close against the angel now, and Sam smiles into his shoulder as the drumming of Dean’s heart fills his ears.

“Does that sound good, Sam?” Castiel asks, and the younger brother warmly breathes his affirmation.

“Yeah, it sounds beautiful.”

That in turn makes Dean smile. “Can I come now, Cas?” he asks quietly, hoping that he’ll be allowed to finish now that’s he’s pleased both of them, but Cas just chuckles and presses an affectionate kiss to his forehead.

“It wouldn’t be much of a game if I just let you both win now, would it?” he says, wrapping an arm around Dean. “But I promise, if you can get your heart beating this fast again for me tomorrow, I’ll let you come. For now, you just let it slow down and get some sleep.”

Dean’s still frustrated and waiting for his erection to go down, but fair’s fair, so he closes his eyes and snuggles closer to Cas. The angel has moved to wrap his arms around both of them while he keeps the stethoscope pressed against Dean’s chest, and Sam still hasn’t moved to take out the earpieces. Cas lets him keep them in. The angel can feel Sam’s heartbeat banging against his side anyway, and Dean’s is thrumming into his fingertips, so he lets Sam fall asleep to the sound of his brother’s heartbeat while he himself becomes lost in the rhythms either side of him. It doesn’t take long for Dean’s heart rate to steady and Cas feels both their heartbeats synchronise. It makes their hearts seem almost tangibly connected, so attuned to each other like the brothers always have been, and Cas thinks there’s no place he’d rather be than lying here between them.

**Author's Note:**

> It did occur to me about half way through this that perhaps I should have had Sam and Dean masturbating each other, and then whoever got the other's heart to beat fastest would get the treat. I could still write that if anyone's interested? Or I'll take any different prompts for more variety.


End file.
